Current studies of quarkonium production phenomenology are based on NRQCD [1]},
a non-relativistic effective field theory whose pillar is the
hypothesis of factorization of the long- and short-distance parts of the production process.
Under this hypothesis, the inclusive prompt production cross section of a quarkonium state \(H\) ,
after a collision of initial systems \(A\)  and \(B\) , can be written as a linear combination
of SDCs (\(\mathcal {S}\) ) to produce heavy quark-antiquark pairs (\(Q \overline{Q}\) )
of different colours (singlet or octet) and spin-angular momentum configurations:
\(\begin{split}\sigma (A+B \rightarrow H+X) =\sum \limits _{S,L,C}& \mathcal {S}(A+B\rightarrow Q \overline{Q} [^{2S+1}L_J^C] +X) \\& \times \mathcal {L}( Q \overline{Q} [^{2S+1}L_J^C] \rightarrow H) \; .\end{split}\) 
